Electric switch



Oct. 11, 1927. 7

7 A. M. KINNEY ELECTRIC SWITCH I Filed June 26.11926 41%, will Patented Oct. 11, 1927'.

UNITED STATES PATENT OFFICE.

ALDON M. KINNEY, OF NORWOOI), OHIO, ASSIGNOR TO THE BRYANT ELECTRIC COM- IPANY, OF BRIDGEPORT, CONNECTICUT, A CORPORATION OF CONNECTICUT.

ELECTRIC SWITCH.

Application filed June 26, 1926. Serial No. 118,689.

My invention relates to electric switches and particularly to switches of the snap action type. The object of my invention is to silence the operation of a switch by cushioning the impact of spring stressed parts.

In the accompanying drawings Fig. 1 is a plan view of a single pole flush switch in which my invention is embodied in one form.

Figs. 2 and 3 are respectively sections on the lines 22 and 3-3, Fig. 1.

Fig. 4: is a perspective of the switch frame and Fig. 5 is a perspective of one of the silencing cushions.

While my invention may be embodied in switch mechanisms of various types, I refer, for the sake of explanation, to a flush switch having the general structural characteristics illustrated in the co-gending application of Carl Eric Anderson, erial'No. 509,242, filed October 21, 1921. It suflices to state that in the Anderson construction the throws of the operating lever 15 and the switch bar rocker 16 are halted by impact against portions of the switch frame 17. Inasmuch as these parts are all metallic, the impacts cause more or less hoise. This is objectionable in many installations, for example in hospitals, offices,

apartments, dwellings, etc., particularly when the switches are mounted as usual in metallic outlet boxes located in partitions. The operation of the switch is commonly audible in adjacent rooms, and sometimes at remote points. My invention provides means to silence the operation of the switch; while maintaining the advantages of standard switch mechanism whether of the type illustrated or other type.

Inasmuch as the mechanism shown is now in common use on the market, except as modified in the particulars hereinafter mentioned to embody my invention. detailed description is unnecessary. Briefly the switch comprises a cup-shaped insulating base 18 in which the switch contacts and mechanism are housed. The open face of the body is spanned by the supporting frame 17, the offset side wings 19 and 20 of which carry the switch mechanism. Between the wings 19 and 20 the top of the frame is open to permit the play of operating lever 15, which is pivoted at 21 adjacent its lower end and is engaged at 22 by one end of the switch spring 23. The U-shaped switch bar rocker 16 ispivoted at 2 1 on the frame and is engaged at 25 by the opposite end of the spring 23. In the present commercial construction, the play of the rocker is limited by stop lugs 26 at the lower margins of the wings 19 and 20.

The throw-of the operating lever 15, as well understood, not only stresses the spring 23, but also shifts it across the axis of oscillation of the switch bar rocker 16 thus cans-- ing the latter to snap across its throw and shift the switch bar 27 into or out of engagement with the fixed contacts 28-29 to open or close the circuit. The impact of the switch bar rocker against the stop lugs 26 of the frame is the principal cause of noise on the operation of the switch. The impact of the operating lever against the frame at the opposite ends of-its throw is less forcible and consequently lessobjectionably noisy. Nevertheless it also is a source of some racket and I prefer to silence its operation as well as that of the switch bar rocker.

For this purpose I provide a. silencing cushion means, preferably in the form of soft rubber abutment blocks 30, backed by the end Walls of the switch chamber and projecting sufficiently into the respective paths of the operating lever and switch bar rocker to receive the impacts thereof toward the ends of their throws without in any way impeding or hampering the usual operation of the mechanism. The single block 30 such as shown in Fig. 5 may be utilized at each end of the switch chamber and may be so "shaped and located that the operating lever atnd switch bar rocker both impinge against 1 I In the form shown, the usual rib or barrier at the end of the switch chamber and integral with the base 18 is omitted and its place is taken by the block 30, which-being also of insulating material serves the same barrier function as the usual rib integral with the base. The block has a depth substantially coincident with the depth of the switch chamber. Its width substantially corresponds to the spacing of the frame wings 19 and 20 between which it lies and by which the block is located transversely in the chamber. Its thickness is such that it projects into the chamber on the one hand beyond the stops 26 (which are spaced somewhat further apart than usual) and on the other hand beyond the lugs 31 at opposite ends of the top opening in the frame. These lugs are inwardly ofiset into recesses 32 formed The blocks are thus maintained firmly inposition by the frame, while the inner faces thereof lie in front of the metallic stops for the operating lever and switch bar rocker. The impact of these spring stressed mem hers is received by the resilient blocks which thus silence the switch operation, without interfering or altering the switch mechanism. The arrangement of the blocks in fixed position places no additional burden upon the switch spring as would be the case were the silencing members mounted upon the rocker 16 or lever 15. Moreover, greater body of rubber can be utilized than if the silencing member were carried by the moving parts, and consequently greater resilience and durability are secured. No hazard is introduced in the switch as would be the case were a metallic cushioning spring employed, since in case of breakage metal might cause a dangerous short circuit, while rubber fragments, even if broken off, would merely impede'the operation of the switch.

While the fixed stops 26 and 31 on the frame might be omitted all together, I prefer to retain them to limit the throw of the switch bar rocker and operating lever and thus keep the switch mechanism in operating condition should the impact portions of the blocks break 03. I have found however that if the blocks are made from soft rubber of good grade their life is ample under ordinary service conditions.

As above stated my invention is applicable to mechanisms. of various types. The construction shown is merely illustrative of my underlying thoughts which may be embodied in various modified forms to meet the exigencies of various switch mechanisms, without departing from what I claim as my invention.

I claim:

1. In an electric switch, a spring-stressed operating leverand a spring-stressed circuit closer, and resilient abutment meanscommon thereto for silencing the throw of each of said members.

2. In an electric switch, an oscillating op- .n'ating lever and an oscillating circuit closer, spring means stressing both of said members, and resilient abutment means common thereto for silencing their throw.

3. In an electric switch, an insulating body" and recessed to receive a switch mechanism, a switch mechanism arranged within said chamber and comprising an oscillating spring-stressed member, and resilient means at opposite ends-of the chamber constituting abutments limiting the throw of said member in opposite directions.

4. In an electric switch an insulating body recessed to afford a switch chamber, a switch mechanism arranged within said chamber comprising an oscillating, springstressed circuit closer, together with resilient means at opposite ends of the chamber constituting silencing abutments which limit the throw of the circuit closer.

5. In an electric switch, an insulating body recessed to afford a switch chamber, a switch mechanism arranged within the chamber and comprising a spring-stressed oscillating member, a frame extending across the open end of the switch chamber, and a resilient abutment for the oscillating member confined within the chamber by said frame member.

6. An electric switch comprising an insulating base, a frame mounted thereon, an

oscillating member mounted in said frame,

and resilientmeans clamped in position by said frame and serving to limit the throw of said switch member.

7 In an electric switch, an insulating base recessed to afford a switch chamber, a frame member within said chamber, a sprin stressed switch member mounted in said frame and resilient means clamped by. said frame against the body member, and constituting an abutment for said switch member.

8. In an electric switch, an insulatin base recessed to afliord a switch chamber, a rame extending across the open end of the switch chamber, and a resilient abutment member secured within the chamber, by said frame.

9. ,In an electric switch, an insulating base, a frame comprising spaced wings shaped to afford stops for an oscillating spring-stressed member, and resilient abutment means backed by said base and arranged between said wings and projecting in front of said stops 'to silence the impact of said oscillating member.

10. In an electric switch, an insulating base recessed to afford a switch chamber," resilient abutments backed by the base at opposite ends of said chamber and aswitch member having a spring-stressed throw halt ed by said resilient abutments.-

11. In an electric switch, an insulating base recessed to afford a switch chamber, and

resilient ribs backed by the end walls of the rubber held against the base by said frame and constituting an abutment to halt said circuit closer in open circuit position.

13. In an electric switch, a chambered insulating body, a switch frame secured to said body, a quick make and break switch mechanism arranged within the chamber of the body, and resilient insulating abutment means clamped in fixed position within the chamber by said frame and lying in the path 7 of certain of the moving elements of the switch mechanism to cushion their throw.

' 14. An electric switch comprising an insulating base, a frame mounted thereon, a quick make and break switch mechanism mounted on the frame and comprising an oscillating member in combination with a block of resilient insulating material engaged in fixed position between the frame and base and projectin into the ath of said oscillating member to alt the t row of the latter.

15. An electric switch com rising a metallic frame having substantial y parallel wing said wind members of the frame, and a switch mechanism comprising an oscillating member of which at least a portion moves in a direction substantially parallel to said wing members and between the latter the throw of said oscillating member being halted by impact against said block.-

'16. An electric switch comprising 'a metallic frame having substantially parallel wing members,-a block of resilient insulating material supported in fixed position between said wing members of the frame, and a switch mechanism comprising a pair of oscillating members each of which has at least a portion which moves in a direction substantially parallel to said wing members and between the latter, the throw of said oscillating members being halted by impact against said block.

In testimony whereof- I have signed by name to this specification.

- ALDON M. KINNEY. 

